The field of the disclosure relates generally to turbofan engines and, more particularly, to systems and methods of reducing the temperature of air in the rotor cavity of a turbine assembly.
At least some known gas turbine engines, such as turbofan engines, include a fan, a core engine, and a power turbine. The core engine includes at least one compressor, a combustor, and a high-pressure turbine coupled together in a serial flow relationship. More specifically, the compressor and high-pressure turbine are coupled through a first drive shaft to form a high-pressure rotor assembly. Air entering the core engine is mixed with fuel and ignited to form a high energy gas stream. The high energy gas stream flows through the high-pressure turbine to rotatably drive the high-pressure turbine such that the shaft rotatably drives the compressor. The gas stream expands as it flows through a power or low-pressure turbine positioned aft of the high-pressure turbine. The low-pressure turbine includes a rotor assembly having a fan coupled to a second drive shaft. The low-pressure turbine rotatably drives the fan through the second drive shaft.
In at least some known turbofans, a portion of air discharged from the compressor is channeled towards a rotor cavity of the high-pressure turbine and the air is used downstream therefrom for cooling purposes. During operation, many modern commercial turbofans generate heat and noise between the surfaces of rotating members of the turbofan and the air surrounding the rotating members. More specifically, the heat generated by the rotating members of the turbofan increases the temperature of the compressor discharge air channeled through the rotor cavity. As such, the cooling efficiency of the compressor discharge air is reduced.